CN207494289U - A kind of shaped structure for manufacturing lightweight automobile rim - Google Patents

Abstract

The utility model discloses a forming structure for manufacturing lightweight automobile wheel rims, which belongs to the technical field of precision forming of large-caliber pipe parts. According to the concave and convex characteristics of the structure of the new lightweight automobile rim parts, a composite hydroforming structure is designed and invented. Through the joint cooperation of the blank and the mold, the inner and outer independent airtight cavities are respectively formed, and the outer high pressure formed rim bottom groove area, Internal hydroforming of the rim flange area, both at the same time. The use of this structure for part forming not only greatly improves the efficiency compared with the traditional rolling process and spinning process, but also can effectively reduce the amount of deformation in a single pass during the forming process of rim parts, and with appropriate axial feed, it can Effectively prevent the excessive thinning of the part wall thickness and ensure the rigidity of the rim structure. The flexible medium of the pulsating liquid provides the required load for forming, effectively ensuring the surface quality of the rim parts and reducing subsequent processing.

Description

A forming structure for manufacturing lightweight automobile rims

technical field

The utility model relates to the technical field of precision forming of tubular parts, in particular to a forming structure for manufacturing lightweight automobile wheel rims.

Background technique

Automobile steel wheels are composed of two parts, the rim and the spokes. The rim is the part around the edge of the steel wheel. The rim, commonly known as the rim, is in contact with the spokes and tires respectively, and is the main load-bearing key component. There are two common forms of automobile rims: deep groove rim and flat bottom rim; in addition, there are split rims, semi-deep groove rims, deep groove wide rims, flat bottom wide rims and full inclined bottom rims. The surface structure of the wheel rim is generally more complex, the amount of deformation is large during the forming process, it is easy to crack and wrinkle, and there are problems such as low material utilization rate and complicated process.

At present, plate rolling welding, multi-pass rolling and expansion finishing are widely used. The manufacturing process is complicated, low in efficiency and high in cost. At the same time, due to the limitation of the process, the wheel rim can only be used in general with medium-strength low-alloy steel, and it cannot be formed into a more complex structure. The shape of the rim parts cannot meet the demand for further weight reduction.

The current forming method is mainly roll forming process. Chinese invention patent CN 103286524A discloses a plate forming rim processing technology, which reduces the weight of the rim itself, reduces the cost and improves the reliability of the product compared with the traditional steel forming process. However, this process still has shortcomings such as long rolling process, relatively large wall thickness of the blank, and excessive rigidity. And it is easy to cause different degrees of scratches on the surface of the parts during the rolling process. During the forming process of the rim parts with asymmetric longitudinal section structure, the stress is more complicated, and the axial force is unbalanced, so it is necessary to add other structures to balance the axial force difference, and the required forming molds are many, and the production cost is high.

Chinese invention patent CN 103464563 A discloses a high-pressure liquid-filled forming device outside a pipe. Although this device adopts hydroforming, the forming effect is good, but it can only form some simple parts, and it is difficult to control the amount of deformation for complex parts.

Although the forming methods of the above two forming processes are different, for the forming of complex tubular parts with large radial deformation, there are disadvantages such as long process flow, small deformation, poor surface quality of formed parts, and low production efficiency.

Utility model content

In order to solve the above-mentioned deficiencies in the prior art in the rim processing technology, the purpose of this utility model is to provide a forming structure for manufacturing lightweight automobile rims, which forms independent inner and outer parts through the joint cooperation of blanks and molds. Closed cavity, in which the outer high pressure forming rim bottom groove area, the inner high pressure forming rim edge flange area, the two are carried out at the same time, with the selection of a moderate outer diameter of the tube blank, and finally realize the complex structure and thin wall with large radial deformation Hydroforming of tubular parts.

In order to achieve the above object, the technical scheme adopted in the utility model is as follows:

A forming structure for manufacturing lightweight automobile rims, the forming structure includes an inner high pressure forming die, an outer high pressure forming die, a cylindrical blank and an annular punch; wherein: the inner high pressure forming die is set outside the outer high pressure forming die, After closing the molds, a closed mold cavity of the automobile wheel rim is formed; a cylindrical blank is placed between the inner high pressure forming die and the outer high pressure forming die, and the annular punches are arranged at both ends of the cylindrical blank, which can make the cylindrical blank Axial feed movement.

The cylindrical blank divides the closed mold cavity into two parts, inside and outside. One side of the inner surface of the blank is an outer high-pressure closed cavity, and one side of the outer surface of the blank is an inner high-pressure closed cavity.

Both the inner high pressure forming die and the outer high pressure forming die are split structures, the inner high pressure forming die is a symmetrical upper and lower split structure, and the outer high pressure forming die is a symmetrical left and right split structure.

The inner high pressure forming mold is provided with a liquid filling channel I, which is arranged along the radial direction of the inner high pressure forming mold, and the liquid outlet corresponds to the inner high pressure closed cavity; the outer high pressure forming mold is provided with a liquid filling channel II, and the outlet The liquid end corresponds to two external high-pressure closed cavities.

The forming structure also includes a sealing ring, which is distributed along the circumferential direction and arranged at a position between the inner high-pressure sealed cavity and the outer high-pressure sealed cavity.

The wall thickness of the cylindrical billet is 2 mm, the outer diameter of the initial tube billet is 360 mm, and the diameter-to-thickness ratio is 180. The low-carbon micro-alloy steel S500MC is used, and its tensile strength is about 650 MPa.

The forming method for manufacturing a lightweight automobile rim by using the forming structure specifically includes the following steps:

(1) Set the cylindrical blank on the outer high pressure forming die, close the inner high pressure forming die and the annular punch, and form mutually independent outer rings on the inner and outer sides of the cylindrical blank through the cooperation of the cylindrical blank and the mold. High pressure airtight chamber and internal high pressure airtight chamber;

(2) Simultaneously apply pulsating high-pressure liquid to the inner and outer surfaces of the cylindrical blank through the liquid-filled channel II on the outer high-pressure forming die and the liquid-filled channel I on the inner high-pressure forming die. At the same time, the annular punch drives the cylindrical blank. The billet is pushed inward until the cylindrical billet is fully attached to the contact surfaces of the inner and outer high pressure forming dies;

(3) Release the high-pressure liquid, exit the ring punch, open the inner high pressure forming mold vertically and remove the outer high pressure forming mold horizontally, and take out the formed rim parts.

In the above step (2), when the pulsating high-pressure liquid is applied to the surface of the cylindrical blank for forming, the load waveforms of the high-pressure liquid applied to the inner and outer surfaces are consistent. The hydroforming medium is water or hydraulic oil.

The beneficial effects of the utility model are as follows:

1. Compared with the traditional rolling forming process, the utility model adopts the internal and external composite hydroforming process, which shortens the original multi-pass rolling into one-pass composite hydroforming, greatly shortens the process flow, and has high forming efficiency. And the formed parts do not need to be shaped, and the forming precision is high.

2. Utilizing the structure of the utility model for part forming not only greatly improves the efficiency compared with the traditional rolling process and spinning process, but also can effectively reduce the deformation amount of a single pass in the forming process of rim parts, and cooperate with appropriate axial Feed can effectively prevent the excessive thinning of the part wall thickness and ensure the rigidity of the rim structure. The flexible medium of the pulsating liquid provides the required load for forming, effectively ensuring the surface quality of the rim parts and reducing subsequent processing.

3. The internal and external composite hydroforming process is adopted, which can reasonably distribute the internal and external pressure forming process. Compared with single internal high pressure forming or external high pressure forming, it can effectively reduce the deformation of the blank, effectively prevent the excessive thinning of the part wall thickness, and increase the strength and rigidity of the formed part.

4. Using the internal and external composite hydroforming process, the forming process is relatively stable. Under the premise of ensuring effective axial feed and selecting higher-strength materials, the wall thickness of the initial blank can be appropriately reduced. Compared with the traditional rolling process, It can effectively reduce the weight of the rim parts and reduce the waste of materials, and the parts after hydroforming have a high degree of fit with the mold, and there is no need to increase the shaping process.

Description of drawings

Fig. 1 is the schematic diagram of the forming structure of the utility model manufacturing lightweight automobile rim.

Fig. 2 is a schematic diagram of the method for manufacturing lightweight automobile rims based on the internal and external pressure composite forming process of the present invention.

Figure 3 is a schematic diagram of the forming process and mold opening of the internal and external composite hydroforming die.

In the figure: 1-inner high pressure forming die, 2-cylindrical blank, 3-annular punch, 4-outer high pressure forming die, 5-liquid filling channel Ⅰ, 6-sealing ring, 7-liquid filling channel Ⅱ, 8- rim parts.

Detailed ways

The utility model is described in detail below in conjunction with accompanying drawing and embodiment. But the utility model is not limited to the composite hydroforming of the following wheel rim parts, and is equally applicable to other wheel rims of the same type with different models and sizes.

The utility model is a forming structure and a forming method for manufacturing lightweight automobile wheel rims based on an internal and external composite hydraulic forming process, and is suitable for forming automobile wheel rims with high strength and large diameter-thickness ratio. As shown in Figure 1, the forming structure includes an inner high pressure forming die 1, an outer high pressure forming die 4, a cylindrical blank 2 and an annular punch 3; In addition, the airtight mold cavity of the automobile wheel rim is formed after the film is combined; the cylindrical blank 2 is placed between the inner high pressure forming die and the outer high pressure forming die, and the annular punch 3 is arranged on both ends of the cylindrical blank, which can make the The cylindrical blank performs an axial feed movement.

The cylindrical blank divides the closed mold cavity into two parts, inside and outside. One side of the inner surface of the blank is an outer high-pressure closed cavity, and one side of the outer surface of the blank is an inner high-pressure closed cavity.

Both the inner high pressure forming die and the outer high pressure forming die are split structures, the inner high pressure forming die is a symmetrical upper and lower split structure, and the outer high pressure forming die is a symmetrical left and right split structure.

The inner high pressure forming mold is provided with a liquid filling channel I5, which is arranged along the radial direction of the inner high pressure forming mold, and the liquid outlet corresponds to the inner high pressure closed cavity; the outer high pressure forming mold is provided with a liquid filling channel II7, and the outlet is The liquid end corresponds to two external high-pressure closed cavities.

The forming structure also includes a sealing ring 6, which is arranged at a position between the inner high-pressure sealed cavity and the outer high-pressure sealed cavity.

In the utility model, the outer high-pressure sealed cavity is a closed space formed by closing the outer high-pressure forming die, the cylindrical blank, the annular punch and the inner high-pressure forming die. The inner high-pressure closed cavity is a closed space composed of the inner surface of the cylindrical blank and the outer surface of the corresponding part of the outer high-pressure forming mold.

In the utility model, the hydroforming medium is water or hydraulic oil.

In the utility model, the inner and outer high-pressure forming molds are respectively designed as two parts which are symmetrical up and down and two parts which are symmetrical left and right, so as to realize the smooth demoulding of the rim part 8 along the radial and axial directions after forming.

In the utility model, four liquid-filled passages are opened on the inner and outer high-pressure forming molds, so as to facilitate fast, efficient and uniform delivery of the forming medium to the forming position.

Example 1:

In this embodiment, the method for manufacturing lightweight automobile rims based on the internal and external composite hydroforming process is as follows (as shown in Figure 2-3):

In the first step, a low-carbon microalloy steel S500MC with a length of 184 mm, a pipe diameter of 360 mm, and a wall thickness of 2 mm is selected, with a tensile strength of about 650 MPa, as the initial cylindrical blank 2 for internal high pressure forming, as shown in Figure 2. The inner high pressure forming die 1 is opened vertically, and the cylindrical blank 2 is installed on the outer high pressure forming die 4 for hydroforming.

The second step is to close the two halves of the outer high pressure forming die 4 in the axial direction, close the two halves of the inner high pressure forming die 1 that are symmetrical up and down in the vertical direction, and feed the annular punch 3 in the axial direction to fix the cylindrical blank 2 in the correct position , lock the inner high pressure forming die 1, the outer high pressure forming die 4 and the ring punch 3 at the specified position, and use the inner surface of the inner high pressure forming die 1, the ring punch 3, the cylindrical blank 2 and the outer high pressure forming die 4 The outer surface forms a closed cavity with internal high pressure and external high pressure on the inner and outer surfaces of the cylindrical blank, and the liquid filling device is activated to fill the closed cavity through the inner high pressure forming liquid filling channel Ⅰ5 and the outer high pressure forming liquid filling channel Ⅱ7. enough liquid.

The third step is to input high-pressure liquid into the closed cavity according to the internal and external high-pressure forming pressure fluctuation loading curve, and make the annular punch 3 perform a corresponding axial feed movement, so that the cylindrical blank 2 and the mold cavity are gradually fitted.

The fourth step is to release the high-pressure liquid, exit the annular punch 3, open the inner high pressure forming die 1 and the inner and outer high pressure forming die 4, and take out the formed rim part 8 to complete the entire forming process.

Claims (6)

1. a kind of shaped structure for manufacturing lightweight automobile rim, it is characterised in that：The shaped structure includes internal high pressure forming die Tool, outer high-pressure forming mold, cylindrical blank and annular punch；Wherein：The internal high pressure forming mold is set in outer high-pressure forming Except mold, the closed die cavity of automobile rim is formed after molding；Between the internal high pressure forming mold and outer high-pressure forming mold Cylindrical blank is placed, the annular punch is set on two end sides of cylindrical blank, and cylindrical blank can be made to carry out axial feed motion.

2. the shaped structure of manufacture lightweight automobile rim according to claim 1, it is characterised in that：The cylindrical blank Closed die cavity is divided into inside and outside two parts, blank inner surface side is outer high-pressure sealed cavity, and blank outer surface side is interior height Press airtight cavity.

3. the shaped structure of manufacture lightweight automobile rim according to claim 1, it is characterised in that：The interior high pressure into Shape mold and outer high-pressure forming mold are all separate structure, and internal high pressure forming mold is symmetrical two-piece unit structure, outer high pressure Shaping dies is symmetrical split left and right structure.

4. the shaped structure of manufacture lightweight automobile rim according to claim 2, it is characterised in that：The interior high pressure into Shape mold is equipped with filling liquid channel I, is set along the radial direction of internal high pressure forming mold, outlet end corresponds to interior high-pressure sealed cavity； The outer high-pressure forming mold is equipped with filling liquid channel II, and outlet end corresponds to two outer high-pressure sealed cavitys.

5. the shaped structure of manufacture lightweight automobile rim according to claim 2, it is characterised in that：The shaped structure is also Including sealing ring, it is set at the position between interior high-pressure sealed cavity and outer high-pressure sealed cavity.

6. the shaped structure of manufacture lightweight automobile rim according to claim 2, it is characterised in that：The cylindrical blank Wall thickness for 2mm, the initial a diameter of 360mm of pipe, radius-thickness ratio 180, using low-carbon micro steel-alloy, tensile strength is about 650MPa。